German Patent No. 40 20 351 describes a method for electronically monitoring and controlling the opening and closing operation of electrically driven units, where acceleration forces, in particular those acting in the vertical direction, are sensed by a sensor to be installed additionally.
German Patent No. 34 13 380 also describes an apparatus for opening and closing a convertible top of a vehicle. At a vehicle speed &gt;3 km/h, an inhibition signal is generated which immobilizes the drive system of the convertible top. A vehicle-speed-dependent limit value for a closing force limiting system is not, however, known.